Pliers

ABSTRACT

A PAIR OF PLIERS COMPRISING A FIRST FIXED RIGID JAW AND AN ADJACENT ELONGATED PIVOTED JAW MOUNTED BETWEEN PROTECTIVE SIDE PLATES. A PERPENDICULAR ROD MOUNTED TO THE FIRST JAW EXTENDS THROUGH THE SECOND JAW AND IS THREADABLY ENGAGED BY A MOVABLE COLLAR. A CAM ASSEMBLY IN THE FORM OF A PIVOTED LEVER IS INTERPOSED BETWEEN THE SECOND JAW AND THE COLLAR. A YIELDABLE SLIDE IS MOUNTED ADJACENT TO THE FIRST JAW FOR SELECTIVELY CLAMPING ARING IN PLACE.

NOV. 16, 1971 w, R DOOR 3,620,108

PLIERS Filed Feb. 13, 1970 i v :i l J A 32 I T 4 AK /6 I4 A6 3 G31 8 30 V" 1 2 l4 INVHNTOR. 4 Wesley R. Door 3,620,198 PLIERS Wesley R. Door, Rio Piedras, Puerto Rico, assignor to USM Corporation, Boston, Mass. Filed Feb. 13, 1970,, Ser. No. 11,214 Int. Cl. B251) 7/04, 7/12 US. Cl. 81341 8 Claims ABSTRACT OF THE DISCLOSURE A pair of pliers comprising a first fixed rigid jaw and an adjacent elongated pivoted jaw mounted between pro tective side plates. A perpendicular rod mounted to the first jaw extends through the second jaw and is threadably engaged by a movable collar. A cam assembly in the form of a pivoted lever is interposed between the second jaw and the collar. A yieldable slide is mounted adjacent to the first jaw for selectively clamping a ring in place.

BACKGROUND OF THE INVENTION This invention is designed specifically for applying substantial compressive forces to a workpiece while positively limiting the amount of inward movement of the plier jaws. The use of conventional pliers for such work is hazardous in many applications where the possibility of the pliers 'accidently slipping and damaging the workpiece involves serious financial loss. To solve this I have developed a pair of pliers with an adjustable collar to positively limit movement of the clamping jaws toward one another. By presetting the limit of such movement, one can insure that subsequent accidental movement of the jaws will not result in damage to the article being worked upon.

SUMMARY OF THE INVENTION The invention essentially comprises a first rigid jaw that has a tapered work engaging configuration at one end and an oppositely-facing second similar jaw. The second jaw is pivotable about a transverse axis with respect to the first jaw. A rod extends from the first jaw through the second jaw substantially along the line of movement of one jaw relative to the other. The rod is freely received through the second jaw. It is threadably engaged by a collar mounted outwardly adjacent to the second jaw. A lever having angular cam surfaces facing the jaws straddles the rod and is located between the second jaw and the collar. The lever extends along the length of the second jaw and can be manually operated to exert pressure between the collar and the second jaw, thereby causing the second jaw to close toward the first jaw.

It is one object of this invention to provide a readily adjustable pair of pliers having jaws limited in movement. The pliers are simple in structure and can be easily set to the precise requirements necessary for the protection of a fragile workpiece.

Another object of this invention is to provide a safe pair of pliers for exerting substantial pressure against a workpiece while providing a positive safeguard against accidental movement of the jaws beyond that amount of movement that can be safely accommodated by the article.

Another object is to provide such a tool in which the jaws can be moved toward one another by turning the collar in a manner similar to the operation of a vise,

United States Patent O ice and in which additional power can be applied by further use of the movable lever.

These and further objects will be evident from the following disclosure and the specific embodiment illustrated in the drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of a pair of pliers embodying the present invention;

FIG. 2 is a view similar to FIG. 1 showing the pliers with the near side plate removed;

-FIG. 3 is a top view of the device shown in FIG. 1; and

FIG. 4 is a sectional view through the device as seen along line 44 in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT The pliers shown in the drawing comprise a first elongated jaw 10 and an oppositely facing second elongated jaw 11. The two jaws 10 and 11 are essentially identica to one another, both being rectangular in cross section. They are substantially the same length. Each includes a tapered work engaging configuration facing one anothe at the outer end of the pliers. The respective work engaging configurations are indicated by the numerals 12 and 13. law 10 is fixed between parallel solid side plates 14 which overlap a substantial portion of each of the jaws 10, 11. The side plates 14 are bent to form a connecting web 15 spaced outwardly from jaw 10.

Jaw 10 is fixed between the side plates 14 by two bolts 16. law 10 can be fixed by any suitable connecting elements, such as screws, rivets, or a suitable adhesive bond or weld. Jaw 11 is pivotally mounted between the side plates 14, a transverse pivot shaft being shown at 17. The transverse pivotal axis of the jaw 11 with respect to the side plates 14 and fixed jaw 10 is located at the end of jaw 11 remote from its work engaging configuration 13.

A straight rod 18 is threadably engaged within an aperture extending through jaw 10. This rigidly mounts rod 18 to jaw 10. Rod 18 extends outwardly from jaw 10 through a slightly oversize hole indicated by dashed lines 20 in FIG. 2. While rod 18 is located so as to extend substantially along the arc of movement of jaw 11 relative to jaw 10, the slightly oversize hole 20 accommodates pivotal movement of jaw 11 without binding.

Located outwardly from the jaw 11 and threadably engaged on the rod 18 is an adjustable collar 21. The collar 21 is threadably mounted to rod 18 for longitudinal adjustment along the length of rod 18.

An elongated lever 22 is mounted outward of jaw 11 and includes an outer end that straddles the rod 18, the rod 18 being movably received within enlarged holes formed through lever 22. The elongated surface of lever 22 that faces jaws 10, 11 includes a first portion 23 and second portion 24 which are angularly offset from one another. They intersect along a transverse line at 25, this line providing a fulcrum between lever 22 and the movable jaw 11. Lever 22 also includes an outwardly facing surface 26 which bears against collar 21 so as to selectively exert force between the collar 21 and movable jaw 11.

To normally urge the jaws apart, there is provided a "compression spring 27 that encircles the rod 18 between jaws 10 and 11, the respective ends of spring 27 being in abutting engagement with jaws 10 and 11. The spring 27 normally maintains jaw 11 a spaced distance from jaw 10, the amount of separation being governed by the longitudinal position of collar 21 on rod 18.

The lever 22 also includes an outer ledge 28 that overlies collar 21 opposite to the engagement of collar 21 by surface 26. The ledge 26 serves to prevent movement of jaw 11 beyond that normally permitted by pivotal application of force by lever 22 along the fulcrum at line 25, since continued manual squeezing of the pliers or direct pressure on lever 22 will be limited by direct engagement of ledge 26 against the outer surface of the collar 21.

While having general application to any manual work the pliers as illustrated were designed specifically for a jeweler, to aid in setting of gems in rings and findings. The tapered work engaging configurations 12 and 13 of the jaws 10, 11 are useful in bending prongs to mount or tighten stones on rings. The gem mounting or findings can be hand held or mounted in a vise. One first sets the collar 21 along the length of rod 18 with the lever 22 fully closed, the separation between jaws 10 and 11 being the minimum that can be accommodated without possible damage to the stone. One can then release lever 22 and engage the prongs or setting material. By applying leverage to the prongs by manipulation of lever 22, one can bend the prongs or setting. The lever 21 provides safety to the gem, since accidental slippage of the jaws will not result in the jaws being closed beyond the preset limits.

For regular use as pliers, the lever 22 is manipulated. Jaws 10 and 11 can also be used as a vise, by simply turning the collar 21 to move the jaws 10 and 11. When used as a vise, the jaws 10, 11 can be subjected to additional pressure by further use of the lever 22, which as illustrated provides a leverage ratio greater than 10 to 1.

During the use outlined above, the screw 18 itself is not manipulated. However, in the specific embodiment shown, the lower end of screw 18 is threadably received through an aperture that extends completely through jaw 10. It bears against a semi-cylindrical slide 30 located between jaw 10 and Web 15. The rear end of slide 30 is movably located by a shaft 34 protruding through an elongated slot 35 and anchored to jaw 10. It is biased by a surrounding compression spring 36. Its forward end is engageable by the abutting end of rod 18. A knurled cap 31 at the outer end of rod 18 permits threaded adjustment of rod 18 relative to collar 21. By manually holding collar 21 against rotation, rod 18 can be adjusted to apply pressure to slide 30 without changing the relative positions of jaws 10 and 11.

Slide 30 is used in the manner shown in FIG. 1. A typical finger ring 33 is slipped over jaw 10 and slide 30. Rod 18 is then rotated to urge the outer end of slide 30 apart from jaw 10, providing a secure inner grip on the ring 33.

For gem setting purposes the jaws 10 and 11 are each apertured as shown at 32, thereby providing access through the jaws for tools such as a burr used to cut a seat in a ring mounting. The burr and its use is not illustrated, but is conventional, being guided by aperture 32 in the jaw 11.

The pliers can be used in a variety of ways, and are particularly adapted for use by a jeweler, who requires precision pressure to manipulate rather intricate and expensive jewelry elements. As a small vise, the jaws can be used to hold any element in the hand, thereby permitting the element to be worked upon by other tools. The jaws can be used to hold findings, such as spring rings, links, etc., and have been proven to be particularly excellent in the holding and tightening of gem rings.

In watchmaking, the pliers might hold and tighten watchband caps, links, etc., without danger of marring the decorative surfaces involved. The pliers can be used in an upright position as shown, or can be inverted with the lever held toward the bottom of the pliers.

Jaw 11 can be completely released from jaw 10 by rotating rod 18 outward so as to threadably disengage rod 18 from the jaw 10. J aw 11 can then be freely pivoted outward from jaw 10 to permit tools to be mounted through the aperture 32. When desired, one or both apertures 32 can be threaded to permit threading engagement with other tools.

While a specific physical arrangement has been illustrated, it is to be understood that the concept of this disclosure is not limited to the features shown, many of which can be modified without deviating from the invention.

Having thus described my invention, I claim:

1. A pair of pliers, comprising:

a first rigid jaw having a work engaging configuration at one end thereof;

a second rigid jaw overlying and adjacent to said first rigid jaw member, said second jaw member having a work engaging configuration at one end thereof complementary to that of said first jaw and being pivotally mounted relative to said first jaw about a transverse axis;

a rod mounted to said first jaw and extending outwardly therefrom through an aperture formed in said second jaw at a location between its work engaging configuration and said axis;

an axially adjustable collar threadably engaged with said rod outward of said second jaw; and

manually operable cam means located about said rod between said collar and said second jaw for selectively exerting pressure on said second jaw member along the axis of said rod by reaction against the collar.

2. A pair of pliers as set out in claim 1 wherein said cam means comprises:

a lever arm having a first surface facing toward and extending along the length of said second jaw; and

a second surface on said lever arm facing said second jaw and straddling said rod, said second surface being angularly offset from said first surface.

3. A pair of pliers as set out in claim 1 further comprising:

spring biasing means operatively interposed between said first and second jaws for urging the respective work engaging configurations thereof apart.

4. A pair of pliers as set out in claim 3 wherein said spring biasing means comprises:

a compression spring centered about said rod with the respective ends thereof in abutting engagement with said first and second jaws.

5. A pair of pliers as set out in claim 1 wherein said jaws are each elongated straight members substantially coextensive with one another;

said cam means comprising:

an elongated lever arm extending substantially along the length of the jaws and having an angular elongated surface engaging the outer surface of said second jaw and an opposed surface engaging the collar.

6. A pair of pliers as set out in claim 5 wherein said lever arm includes first and second portions of the elongated surface angularly offset from one another along a transverse line that bears against said second jaw as a pivotal fulcrum for the lever.

7. A pair of pliers as set out in claim 1 further comprising:

first and second side plates fixed to said first jaw overlying and partially enclosing said first and second jaws; said second jaw being pivotally mounted to said side plates about said axis. 8. A pair of pliers as set out in claim 7 wherein said side plates are transversely joined outwardly of and spaced from said first jaw; and

6 slide means mounted between said side plates outwardly 2,822,715 2/ 1958 Raimondi 81-3835 X adjacent to said first jaw, said slide being selectively 2,822,715 7/1966 Evans 8 1--383.5 X abutted by the adjacent end of said rod.

ROBERT C. RIORDON, Primary Examiner References Cited 5 R. V. PARKER, JR., Assistant Examiner UNITED STATES PATENTS 1,445,710 2/1923 Rathbone et a1. 81-43 2,566,695 9/1951 Cormieretal 81-43X 81-303, 383-5 

